6. Julianne Hough
The actress is often spotted working up a sweat on one of L.A.’s many scenic trekking spots. However she absolutely took it to the next level when she teamed up with survival guru Bear Grylls for a hiking journey in Africa. “I had so much fun, learned a great deal about nature and survival, and got to explore a side of myself I never knew I had,” she wrote on her blog.